A conventional satellite television receiving system is a satellite ground receiving station consisting of a paraboloid antenna, a feed source, a low noise block, and a satellite receiver. The paraboloid antenna is responsible for reflecting satellite signals to the feed source and the low noise block which are located at a focal point. The feed source is a horn arranged at the focal point of the paraboloid antenna and is used to collect satellite signals. The feed source is also called a corrugated horn. The feed source has two main functions: first, collecting electromagnetic wave signals received by the antenna, converting the collected signals into a signal voltage and supplying the voltage to the low noise block; and second, performing polarization conversion for the received electromagnetic wave. The low noise block LNB (also called a frequency de-multiplier) is used to perform frequency de-multiplication for the satellite signals from the feed source, amplify the signals, and transmit the amplified signals to the satellite receiver. Generally, the LNB includes an LNB of a C wave band frequency (3.7 GHz to 4.2 GHz, 18 to 21 V) and an LNB of a Ku wave band frequency (10.7 GHz to 12.75 GHz, 12 to 14 V). The working flow of the LNB is firstly amplifying the satellite high frequency signals by a hundred thousand times, and then using a local oscillating circuit to convert the high frequency signals into signals at a medium frequency of 950 MHz to 2050 MHz, to facilitate signal transmission on a coaxial cable and signal demodulation and operation of the satellite receiver. The satellite receiver is used to demodulate the satellite signals transmitted from the low noise block. Satellite television images or digital signals and accompanying sound signals are acquired by modulation.
When the satellite signals are being received, the parallel electromagnetic waves are converged onto the feed source after reflection by the paraboloid antenna. Generally, the feed source corresponding to the paraboloid antenna is a horn antenna.
However, since a curved face of a reflective surface of the paraboloid antenna is difficult in machining and high in accuracy requirement, the paraboloid antenna is hard to be manufactured and high in cost.